Zearalenone and its derivatives are the basic Resorcylic Acid Lactone (RAL) compounds used as the starting materials for the compounds of the present invention. Zearalenone may be prepared by culturing the zearalenone producing strain of Gibberella zeae as taught in U.S. Pat. No. 3,196,019, incorporated herein by reference. Zearalenone and its ring-opened and other derivatives have been reviewed in the literature. Shipchandler, Heterocycles, 3(6):471-520 (1975) and Hidy et al "Zearalenone and Some Derivatives: Production and Biological Activities", Adv. Appl. Microbiol., 22:59-82 (1977).
Zearalenone has been chemically modified to form numerous derivatives. U.S. Pat. No. 3,239,348, incorporated herein by reference, discloses a method for producing zearalenol from zearalenone by reducing the ketone carbonyl group. U.S. Pat. No. 3,239,345, incorporated herein by reference, discloses a method for producing zearalanol and its derivatives from zearalenone and zearalenol by reducing the ketone carbonyl group and/or the macrocylic ring double bond. U.S. Pat. No. 4,690,948, incorporated herein by reference, discloses a method for producing ring opened compounds from zearalanol and its derivatives. Numerous other patents and literature references detailing methods for preparing derivatives of zearalenone, zearalenol, and zearalanol are known in the art.
These compounds have generally been used to improve growth performance in animals. These compounds, however, have not previously been shown to be insect chemosterilants.
Numerous insecticides which affect the survivability and reproducibility of houseflies are known. For example, U.S. Pat. No. 1,974,689 discloses esterified carboxyl compounds useful for killing or eliminating flies; U.S. Pat. No. 3,247,055 discloses the use of triphenyltin compounds to control the ability of houseflies to effect sterilization during mating; U.S. Pat. No. 4,515,808 discloses organic compounds useful for combatting infestation with houseflies; U.S. Pat. No. 4,535,076 discloses organophosphate pesticides useful against houseflies; and U.S. Pat. No. 4,413,010 discloses carbamic acid compounds useful against houseflies. Numerous other insecticides are known to those skilled in the art.
There is a continuing need for new compounds that can reduce insect reproduction and therefore control the insect population, particularly the common housefly (Musca domestica).